Akira speaks very accurate truth. I've been playing for 3 years and I'm pretty much just now having an easier time understanding things. I'll save you trouble and tell you that if you sit there and listen to various notes and try to memorize them then you're wasting valuable time that could be spent developing other skills. A perfectly trained ear is a pretty high on the list thing to shoot for. But dammit to hell if I'm not going to 100% encourage you to listen your best asap. That's the primary thing you have to do is listen. The rest is just over time.